In the prior art, various techniques have been used to improve the performance of climate control units, such as an air conditioner (AC) or heating units.
3D sensors have been used to obtain 3D location information. 2D cameras have also been used, but not for estimating 3D locations. 2D sensors other than cameras, such as motion sensors, have not been used to obtain 3D locations.
U.S. Pat. No. 6,645,066, “Space-Conditioner Control Employing image-Based Detection of Occupancy and Use,” uses a conventional 2D camera to detect an occupancy rate, an occupant activity rate, and an occupant activity class. That system only counts people, but does not determine the locations of the people in the environment.
U.S. Pat. App. Pub. No. US 200910193, “Person Location Detection Apparatus and Air Conditioner,” uses a time-of-flight (TOF) 3D sensor to determine 3D locations of people in an environment. The publication describes a TOF sensor, and provides a method for detecting a person at a location given a time sequence of depth maps to control an AC unit.
In U.S. Pat. No. 5,634,846, “Object Detector for Air Conditioner,” motion detection is performed with an infrared (IR) sensor with a Fresnel lens. The system detects the amount of motion in different zones in a field of view of the sensor, which provides very rough information about the 2D locations of people.
Jap. Pat. JP02197747 uses a thermal IR camera to detect people and determine their 2D locations to control an air flow from an AC unit. 3D locations are not described.